While guidance on scenarios involving introduced and translocated
populations are provided inthe
Guidance Document, a few aspects will be discussed here as it may
affect how you quantify the number of extant populations for the
species. Specifically, in the case of introductions, an assessor must
make the determination as to whether a population represents its own
‘native’ gene pool (e.g. the gene pool that existed prior to the
introduction) or whether the population is made of individuals from
another population (and/or may have been through bottlenecks,
translocations and mixing from other populations). In the latter case,
the ‘population’ is being created in space/ geography, but the original
genetic lineage of that space (population A) no longer exists. We
consider that in such cases, the genetic composition now at population
A’s location would not represent the original population A. Thus, the
individuals now at location A should be considered as an expanded Nc of
the lineage that it is being translocated from (e.g., Population B).
This information should be factored into the details of Population B and
NOT provided as a separate population or part of Population A.
Population A should be considered extirpated as its original genetic
composition is not restored. On the other hand, restoration may be
taking place with individuals originally obtained from population A and
kept ex situ and then used for restoration. In this instance, this
population may be considered a translocated Population A. Please clarify
these details in Q48.
If multiple estimates of Ne or Nc exist for a given population, and the
assessor, to the best of their knowledge, cannot determine which would
be the most appropriate or accurate to report on, then the assessor will
need to complete the entire Kobo form for the same species again noting
these alternative population size estimates. A specific noteMUST be made on both forms explaining the situation so that
evaluators can be made aware and review the records together. The
evaluator may then average the available population sizes for that
population as a final estimate.